During the Vietnam War when M-16s were jamming in combat, the US Army took steps to correct the problem. More training on cleaning the weapon was instituted along with issuing mroe cleaning kits. Chroming the whole bolt to reduce fouling was another corrective action. The M-16 has gone on to rack up an impressive service record.
When the M-247 Sgt. York DIVAD proved it could not even hit a stationary helicopter, the whole program was cancelled. It never entered service.
Or of more recent vintage is the Crusader SPG. It was designed for the battlefields of Europe as Warsaw Pact forces poured through the Fulda Gap. Instead it faced a post Desert Storm world where Rumsfeld cast a gimlet eye at the whole program. It was revealed to be overweight and overbudget without a real mission. It was cancelled.
There seems to be another weapon in the arsenal of the US Army that needs to go. When a soldier raises their right hand to swear/affirm to protect the Constitution from all enemies foreign or domestic, they become the most fearsome weapon this country possesses to defend itself. Except now some of these soldiers are saying no to orders. There are those of the Muslim faith that are refusing lawful orders on the basis of their faith. Since the US has a volunteer force, why are these people even in the military? They are giving false service after swearing falsely, and as Akbar, who tossed a grenade into a tent where his friends slept killing three, Yonathan Melaku, and Nidal Hasan have shown, they are potential threats to the lives and safety of their fellow soldiers just like defective weapons failing in the heat of combat.
Note - Thanks to ORD and Lysol for catching my goofs. Any that still slipped through are all mine.